Klipsch Reference Series RT-12d 12-inch Digitally Controlled Subwoofer - BLACK Maximum Acoustic Output - 120dB @ 30Hz 1/8 space, 1m / Frequency Response 19-120Hz +/-3dB Amplifier Power - FTC Rated Power - 800 watts continuous @ &lt;2% THD / Dynamic Power - 2000 Watts Drive Components - Ultra-High-Excursion 12 (30.5cm) Cerametallic Cone, Front-Firing WooferDual Ultra-High-Excursion 12 (30.5cm) Cerametallic Cone, Rear-Firing Passive Radiators Amplifier Type - BASH digital hybrid Enclosure Type - Bass-Reflex Via Dual Rear-Firing Passive Radiators